I know that back when racing gas was cheap and easy to get back in the early '90's, I would put some in my 9.3 compression 440 and the car ran OK.

I did find that I had to reset the float levels in the carb though. The other thing I noticed was that the engine ran rougher and at a higher decibel with pump gas vs. race fuel.

Often I would fill the tank at the track with the lowest octane leaded race fuel and run the car. It was only a little more in cost per gallon at a U.S. track compared to what pump gas cost in Canada.

The car ran so smooth and quiet with race fuel that I could actually have a conversation with someone in the car. With pump gas there would be yelling back an forth. The benefits of leaded race fuel would last for several tanks it I topped off the tank with pump gas several times while driving it on the street. It seemed to work for a couple of weeks which proves that I only needed the lead or a minimum octane boost to keep the engine happy.

I wish they still made gas like that at an affordable price.

--------------------Too many cars, too many parts, too little coin, too little space to work in, too little time left to make it all happen!

Update: down to one ride, still too many parts, a little more jingle in the pocket, gaining space, and it's going to happen this year!